What would you do?

How much is very expensive?
If that procedure got me just 1 mpg more say from 20 to 21 mpgs(Can), up here that is a $650C bucks saved at the pumps in just 50,000 miles,( about 4 to 5 years for me) at today's cost of fuel. And in the meantime, I would get to enjoy whatever extra power it might make at the lesser leakdown.
I understand what you re saying, and, I'm not trying to be argumentative, but sometimes a guy might be willing to spend a bit of money today,to get double or triple or more back over the life of the project. Or maybe just I would,lol.

BTW those were some pretty ugly LD numbers, for sure